Liam Tancock ended Great Britain's world championships in some style, winning the 50m backstroke and breaking his own world record as he did it. Tancock has set the world mark at the distance three times in the past 18 months, but he had never before won a gold medal at a major meet. It was Britain's third swimming gold of the World Championships, and their eighth medal overall, as well as the first for one of the British men.

Tancock, a 25-year-old from Exeter, had never quite fulfilled his enormous potential in a major meet until now. He won a pair of bronzes at the previous world championships, and finished sixth in the 100m in Beijing. He was joint-fourth in the 100m here in a new British record, an experience he described as "bittersweet".

Oddly, given what he had just achieved, Tancock was a little reticent in his celebrations. But he is a taciturn man, not prone to gushing or shouting. After winning he simply stuck up a thumb at his parents in the crowd.

He was muted because the 50m is not his main event. More tellingly perhaps, it is not an Olympic event. How he must wish that was not the case. He has broken the world record twice in two days now. He lowered the record to 24.08sec in the semi-finals, and took another four hundredths of a second off that time in the final. No one else got close.

For Tancock though the task is to translate his form here into the 100m backstroke. He finished joint-fourth in that final earlier this week. "I'm ecstatic," he insisted a little unconvincingly afterwards, "But this is a bonus event. I've picked up a medal here but I just missed out by nine-hundredths in the 100m, and that's what I'm always practising for."

He then revealed he had not swum the distance competitively in over 15 months. "I haven't actually properly done a 50m backstroke since I broke the world record in April 2008, it had been broken again since then, and I wanted it back."

Otherwise it was a disappointing night in the pool for Britain. Tancock's was one of six finals in which the team had representatives, but the only one to return a medal. The closest, and cruellest, of the other final races was Hannah Miley in the 400m individual medley. She came fourth, in a time of 4min 32.72sec, over a second down on the European record she set earlier this year.

Miley had gone into the final turn in third place after producing a brilliant 100m breaststroke. Just behind her though was Australia's Olympic champion Stephanie Rice, and her experience told as Miley tied up in the final 50m, and was beaten to the bronze by no more than a finger's length. Only 19, Miley is one of the most promising swimmers in the British team.

There was disappointment too for Thomas Haffield in the men's 400m individual medley. Having broken his own British record in the semi-final, Haffield found the heat of his first major final a little to fierce and finished joint-last, in a time over two seconds slower than the one that put him through to the final.

Fran Halsall was unable to add another medal to her silver in the 100m freestyle in the 50m version, finishing fifth. The men's 4x100m medley relay team were disqualified, but would have finished in eighth place regardless.

David Davies trailed in sixth in the 1500m freestyle. The 1500m is the only event in which a world record set before the introduction of the Speedo LZR in February is still standing after these championships. Grant Hackett's time of 14min 34.56sec, which the Australian set back in 2001, is the last bastion of that era, the only record that the new swimsuits was unable to break. In total there have been a staggering 43 world records set at these championships.

Mike Scott, the GB performance director, estimated that 95% of his team had switched suits during the last week. He welcomed the restrictions that will come in next year, saying that the sport was moving "from technology to technique". With that in mind, a technique adviser is going to be appointed to work with the British team from October.